Air Force studies blended wings

Researchers test a 21-ft-wingspan prototype of the X-48B, a blended-wing body aircraft, in the Langley full-scale tunnel. Boeing Phantom Works teams with NASA and the Air Force Research Laboratory to study the structural, aerodynamic, and operational advantages of the advanced aircraft concept for potential as a multirole, long-range military aircraft.

The X-48B is an advanced-concept, fuel-efficient blended-wing body, or BWB. It looks more like a modified triangular-shaped wing than a traditional aircraft.

The 8.5%-scale prototype is being tested in the wind tunnel at NASA's Langley Research Center in Hampton, Va. Boeing Phantom Works Advanced Research and Development Unit is working with NASA and the U.S. Air Force Research Laboratory at Wright-Patterson Air Force Base to explore the structural, aerodynamic, and operational advantages of the blended wing.

"The biggest difference between this aircraft and the traditional tube-and-wing type is the lack of a tail," says Dan Vicroy, senior research engineer at NASA Langley. Wind-tunnel tests will show how multiple control surfaces affect the vehicle.

The team has produced two high-tech prototypes of the BWB, built to Boeing's specifications by Cranfield Aerospace in England, for wind-tunnel and flight-testing. The Air Force designated the vehicle the "X-48B" based on the design's potential as a multirole, long-range military aircraft.

"X-48B prototypes have been dynamically scaled to represent a much larger aircraft and to demonstrate that a BWB is as controllable and safe during takeoff, approach, and landing as a conventional military transport," says Norm Princen, chief engineer for the X-48B program.

Boeing engineers say the concept is about 30% more fuel efficient than a conventional airplane of similar size carrying the same payload.

Industry sources say a blendedwing-body military aircraft could be in service within 10 to 15 years, if testing and program funding go well.